An exposure apparatus, which performs the projection exposure onto a photosensitive substrate with a pattern formed on a mask, is used in the photolithography step as one of the steps of producing microdevices such as semiconductor devices and liquid crystal display devices. The exposure apparatus includes a mask stage for supporting the mask and a substrate stage for supporting the substrate. The pattern of the mask is subjected to the projection exposure onto the substrate via a projection optical system while successively moving the mask stage and the substrate stage. In the microdevice production, it is required to realize a fine and minute pattern to be formed on the substrate in order to achieve a high density of the device. In order to respond to this requirement, it is demanded to realize a higher resolution of the exposure apparatus. A liquid immersion exposure apparatus, in which a liquid immersion area is formed by filling the space between the projection optical system and the substrate with a liquid to perform the exposure process via the liquid of the liquid immersion area, has been contrived as one of means to realize the high resolution, as disclosed in International Publication No. 99/49504.